KIT-ENGINE OVERHAUL 20R0641 - Caterpillar

Test the Fuel Injection Nozzles
Table 1
Required Tools
Part Number Part Description Qty
5P-4150 Nozzle Testing Group 1
5P-7448 Adapter 1
6V-2170 Tube Assembly 1
8S-2270 Fuel Collector 1
1U-8857 Extension 1
6V-6068 SAE J-967 Calibration Fluid 1 Perform the following procedures in order to determine if a fuel injection nozzle does not work correctly.Bench test the fuel injection nozzles at a temperature of 18° to 20 °C (64° to 70 °F).
Illustration 1 g00293085
(1) Connection for the nut (not shown) of the fuel supply line
(2) Threaded hole for the banjo bolt of the fuel return line
(3) Nut of the fuel injection nozzle
(4) Wire clip
(5) Seat washer
Illustration 2 g00313043
Fuel injection nozzles and lines
(1) Nut for the fuel supply line
(2) Banjo bolt
(6) Fuel supply line
(7) Fuel return line
Run the engine at low idle.
Loosen the nut for fuel supply line (1) at the fuel injection nozzle on cylinder number 1. Listen for the low idle to decrease or become rough. Tighten the nut for the fuel supply line (1) on cylinder number 1. Perform this test on each cylinder.
The fuel injection nozzle is faulty when the fuel supply line (1) is loosened and the following events occur:
The engine rpm does not decrease.
The engine does not idle roughly.Remove the fuel injection nozzle for additional testing.Note: If leakage occurs at the nut for fuel supply line (1), make sure that fuel supply line (6) and the nut for fuel supply line (1) are correctly aligned with the inlet connection of fuel injection nozzle (1). Do not tighten the nut for fuel supply line (1) on the high pressure fuel line more than the recommended torque. If the nut is tightened more, the fuel line may become restricted or the threads of the fuel injection nozzle and the nut may be damaged.Cleaning of the Fuel Injection Nozzles
Before a fuel injection nozzle is tested, remove any loose carbon from the tip of the fuel injection nozzle. Do not use abrasive material or a wire brush in order to clean the nozzle.The fuel injection nozzle is not a serviceable part. Disassembling or adjusting the nozzle will violate the standards for emissions.Note: Extra care should be used in handling the fuel injection nozzle in order to prevent damage to the nozzle tip. A scratch or a burr could cause needle leakage or spray distortion. Dirt in the orifices of the nozzle tip can damage engine components. Dirt can also distort the spray pattern of the nozzle.Pressure Test
Ensure that you wear eye protection at all times during testing. When fuel injection nozzles are tested, test fluids travel through the orifices of the nozzle tip with high pressure. Under this amount of pressure, the test fluid can pierce the skin and cause serious injury to the operator. Always keep the tip of the fuel injection nozzle pointed away from the operator and into the fuel collector and extension.
Illustration 3 g00322849
5P-4150 Nozzle Testing Group
(8) 5P-7448 Adapter
(9) Fuel injection nozzle
(10) 6V-2170 Tube assembly
(11) 1U-8857 Extension
(12) 8S-2270 Fuel collector
(13) 8T-5313 Filter
Do not